Late Quaternary activity of the Scorciabuoi Fault (southern Italy) as inferred from morphotectonic investigations and numerical modeling

摘要

Following a detailed morphotectonic analysis of the fluvial terraces of the Sauro River (Basilicata, southern Italy), the present research documents for the first time the late Quaternary tectonic activity of the Scorciabuoi Fault and discusses its inferred seismogenic potential. On the basis of both remote sensing techniques and detailed field investigations, four fill terraces have been recognized and mapped along the Sauro Valley showing differential cumulative displacements across the fault. These terraces are genetically correlated with four highstand sea level periods. Following stratigraphic and geological age constraints and on the basis of the correlation with a sequence of marine and fluvial terraces characterizing the lower Agri Valley, the Sauro terraces likely formed between 80 (or 100) ka and Present. The inferred long-term slip rate of the Scorciabuoi Fault ranges between 0.5 and 1.0 mm/a. Numerical simulations based on a crustal elastic deformation model also contribute to separate and tentatively quantify the regional uplift rate (～1.0-1.4 mm/a) and to improve the overall reconstruction of the late Quaternary evolution of the area. The synergic but distinct roles played by eustatism, regional uplift, and faulting are eventually appreciated.